Slow Down for Manatees by Jim Arnosky

From chapters.ca:
Manatees are the gentle giants of southeastern coastal waterways. An endangered species, their biggest threat is humans, who unwittingly hit them with their boats in shallow waters. Jim Arnosky's conversational narrative tells the story of one such accident, which leads the manatee to be taken to a rescue and rehabilitation facility. There they discover that the manatee is pregnant. And while she recovers and gives birth to a healthy baby, she longs to be free. Ultimately, both manatees are released into the wild - a huge success for the people who intervened in saving the animal.